Dataset of radiant light energy measurements.This dataset includes radiant light energy measurements from a study by Columbia University's EnHANTs (Energy Harvesting Active Networked Tags) project.date/time of measurement start: 2009-08-14date/time of measurement end: 2010-11-23collection environment: To characterize indoor energy availability , since 2009 we have been conducting a light energy measurement study in office buildings in New York City. In this study we take longtermmeasurements of irradiance (I, in units W/cm^2) in several indoor locations, and also a set of shorter-term indoor/outdoor mobile device measurements.network configuration: For the measurements we use TAOS TSL230rd photometric sensors installed on LabJack U3 DAQ devices. These photometric sensors have a high dynamic range, allowing capturing of widely varying irradiance conditions. We verified the accuracy of the sensors with a NIST-traceable Newport 818-UV photodetector.data collection methodology: Long-term data was collected in static locations on campus of ColumbiaUniversity. Shorter-term experiments were collected by mobile devices.There are multi-day interruptions in data due to power interruptions and device malfunctions.Tracesetscolumbia/enhants/energyRadiant light energy measurements collected by Columbia University's EnHANTs project.description: This traceset includes radiant light energy measurements collected from 2009 to 2010 in a study by Columbia University's EnHANTs project. measurement purpose: Energy-efficient Wireless Networkmethodology: Since June 2009, we have been recording irradiance every 30 seconds in several different static locations using TAOS TSL230rd light-to-frequency converters installed on Lab-Jack U3 Data Acquisition boards. We also conducted several short-term experiments where measurement was conducted by sensor devices as they were moved around New York city.